Add support for read-only address

[samsiegart]

What is the Problem Being Solved?

We want to be able to use the UI with a multisig. Since this isn't possible with keplr, we can add support for connecting with an arbitrary address via url-param, and instead of signing messages with a signer, print them to the console so they can be imported into the multisig tool elsewhere.

Description of the Design

Add support for a new url param address which bypasses keplr and just loads the app in a read-only mode. When the user tries to sign a transaction, just print the message to console so it can be copied.

Security Considerations

This makes it easier for a user to view vault info for other accounts but they can't actually manipulate them, and the data is already public if you know how to query it.